The invention relates to a technology of obtaining an object workpiece by working a work material in a way that controls a cutting machine on the basis of design information defined on a computer.
There has hitherto been known a device contrived to automatically perform working by controlling a working machine on the basis of CAD data, etc. For instance, there is proposed a control device for a machine tool that includes tool route determining means for: inputting workpiece data about workpiece configuration data concerning a final workpiece configuration and workpiece data about a material and a configuration of the workpiece; generating a workpiece working tool route on the basis of data stored with machine s data containing characteristics of a machine body such as a column, a bed, etc. of the machine tool, and tool s data about a working tool which contain a deformation, etc. at a working time when this tool is attached to a holder; and determining working conditions such as a rotating speed of a main shaft, a feeding speed, etc. of the machine tool.
In the conventional device, a working process is determined by a predetermined algorithm which involves using generally three-dimensional CAD data and databases, thereby actualizing automation and standardization. In this case, contents of the database are not automatically updated unless a man changes them, and a result of working is not reflected in the contents of the database. Further, for adjusting the working process outputted from a system it was required that a man having special knowledge adjusts the database.
Therefore, a so-called condition library is main as the database, and there was no system having, as intra-system function, a role performed by an operator such as optimizing the conditions and storing working phenomena, and automatically generating NC data by optimally combining these pieces of information.
Further, as to a so-called feedback system, there exists a working condition correcting device for measuring dimensions of a plurality of workpieces, obtaining an error between a value of this time and a value of the last time of a specified value thereof, and correcting it, however, there exists none of devices used for correcting a feed and the number of revolutions of a working machine in real time while monitoring a main shaft load and working phenomena such as a chatter, etc. during cutting of one workpiece or for correcting the cutting conditions when working next time.
Moreover, in a conventional working control device, a feedback of the result of working to the database is intended for what can be expressed as a measured numerical value such as the number of revolutions, a feed speed, a working time, a dimensional accuracy, etc., wherein an intention and a judgment of the operator is not reflected therein as in a case where if preferable of fitting to other parts, an acceptance is gained even when, for instance, the measured value deviates from a dimensional tolerance, and a case where it is sufficient if a molding product is separable from a die even when the surface roughness of an insert part of a molding portion is rougher than a designated value in a resin molding product die assembly.
Moreover, the tool and the process have hitherto been determined from an experience of the operator. In a three-dimensional CAM that is widely utilized at the present, it is not yet automated as to which tool is used and which process this tool is used.
Note that there was proposed a system having a function of designing the working process based on the database stored with a type of a product to be worked, a tool and a process in a way that makes them mapping to each other, however, there is not any system for designing the working process from a tool library retaining a given 3D configuration without having such a type of database.
Further, a system exists, wherein a small tool is determined by calculating a cutting quantity and a cutting residual in sequence from the largest diameter, however, there is no system for calculating a maximum tool diameter that should be used, from a minimum tool diameter that is to be used by the operator for finishing, and a great deal of experiences of the operator were needed.